Force adjustment mechanism for stationary exercise equipment

ABSTRACT

A stationary exercise device includes a support structure and one or more input members such as pedals, handles, or other feature movably connected to the support structure. A movable output member such as a wheel is movably mounted to the support structure, and operably connected to the one or more input members such that movement of the one or more input members causes the output member to move. A resistance member interacts with the output member when the output member is moving to generate a variable resistance force tending to prevent movement of the output member. The variable resistance force may at least partially simulate the effects of inertia and/or momentum.

BACKGROUND OF THE INVENTION

Various types of stationary exercise equipment have been developed. Known stationary exercise bicycles (“bikes”) may include adjustable force-generating mechanisms that provide resistance to a user pedaling the stationary bike. Cycle trainers are another type of stationary exercise equipment. In general, cycle trainers attach to a bicycle intended for outdoor use (“road bike”) and support the rear wheel of the road bike so it remains stationary while providing resistance to a user pedaling the road bike. However, known devices may suffer from various drawbacks.

SUMMARY OF THE INVENTION

One aspect of the present disclosure is a cycle trainer for generating a resistance force in a bicycle when the bicycle is connected to the cycle trainer. The cycle trainer includes a support structure having a forward portion and a rear portion. The support structure is configured to engage and support a bicycle in a stationary position in which a rear wheel of the bicycle does not engage a floor surface when the rear wheel rotates about a rear axis of the bicycle. The cycle trainer includes a bracket structure that is pivotably connected to the support structure for rotation about a first axis. The cycle trainer further includes a roller having an outer diameter. The roller is rotatably mounted to the bracket structure for rotation about a second axis that is spaced apart from the first axis. The cycle trainer further includes a resistance mechanism that is configured to provide a resistance force that resists rotation of the roller. The roller is configured to engage a rear tire of a bicycle at a contact point to define a force tangent line extending through the contact point that is tangent to an outer diameter of the rear tire and the outer diameter of the roller. An effective lever arm line is defined that extends linearly through the contact point and the first axis. The force tangent line and the effective lever arm line define an acute angle there-between such that a compressive force is applied to the bracket structure by the roller during use of the cycle trainer.

Another aspect of the present disclosure is a stationary exercise device. The stationary exercise device may comprise a cycle trainer, or it may comprise a stationary exercise bike. The stationary exercise device includes a support structure and one or more input members such as a pair of pedals movably connected to the support structure. A wheel is rotatably mounted to the support structure, and operably connected to the pedals such that movement of the pedals causes the wheel to rotate. An arm is pivotably mounted to the support structure, and a resistance member is mounted on the arm. The resistance member interacts with the wheel when the wheel is rotating to generate a variable resistance force tending to prevent rotation of the wheel. Changes in force is applied to the pedals cause the arm to pivot and change the resistance force. The changes in the resistance force can be utilized to simulate the effects of momentum experienced by a rider pedaling a moving road bike.

These and other features, advantages, and objects of the present invention will be further understood and appreciated by those skilled in the art by reference to the following specification, claims, and appended drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is an isometric view of a bicycle mounted on a cycle trainer;

FIG. 2 is a fragmentary, enlarged view of a portion of the cycle trainer of FIG. 1;

FIG. 3 is a fragmentary cross sectional view of a height adjustment mechanism of the cycle trainer of FIGS. 1 and 2;

FIG. 3A is an end view of the height adjustment mechanism of FIGS. 2 and 3;

FIG. 3B is a cross sectional view of a lower portion of the height adjustment mechanism of FIG. 2;

FIG. 4 is a schematic view of the cycle trainer of FIGS. 1 and 2;

FIG. 5 is a partially fragmentary isometric view of a cycle trainer having a fixed eddy magnet that generates a resistance force;

FIG. 6 is partially fragmentary isometric view of another embodiment of a cycle trainer having an eddy magnet that generates a variable resistance force; and

FIG. 7 is a partially schematic side elevational view of a stationary exercise bike.

DETAILED DESCRIPTION

For purposes of description herein, the terms “upper,” “lower,” “right,” “left,” “rear,” “front,” “vertical,” “horizontal,” and derivatives thereof shall relate to the invention as oriented in FIG. 1. However, it is to be understood that the invention may assume various alternative orientations and step sequences, except where expressly specified to the contrary. It is also to be understood that the specific devices and processes illustrated in the attached drawings, and described in the following specification, are simply exemplary embodiments of the inventive concepts defined in the appended claims. For instance, the inventive concepts may apply to other exercise devices, including those which reduce movement to rotary motion at a wheel such as ellipticals, cross trainers, rowers, and other exercise machines, which allow alternative forms of movement. Hence, specific dimensions and other physical characteristics relating to the embodiments disclosed herein are not to be considered as limiting, unless the claims expressly state otherwise.

With reference to FIG. 1, a cycle trainer 1 may be utilized in connection with a bicycle or “road bike” 3. Bicycle 3 may have a conventional construction including a frame 4, seat 5, handle bar 6, and front and rear wheels 7 and 8, respectively. The wheels 7 and 8 may include rims 9 and 10, respectively, and tires 11 and 12. Bicycle 3 may include a conventional drive system 15 including one or more movable input members such as a pair of pedals 16, crank 17, chain 18, and gears 19. In use, a user applies force to the pedals 16 to rotate the rear wheel 8 in a known manner. It will be understood that various types of known bicycles may be utilized in connection with cycle trainer 1.

Cycle trainer 1 includes a support structure such as frame 20. The frame 20 includes angled rear frame members 22A and 22B that are connected to angled front frame members 24A and 24B. A cross member 26 extends between and interconnects the angled rear frame members 22, and includes spaced-apart floor-engaging portions such as first caps 28A and 28B that are configured to engage a floor surface 32. Second caps 34A and 34B are positioned on ends 36A and 36B of angled front frame members 24A and 24B to support a forward portion 38 of frame 20 on floor surface 32. Frame 2 may be constructed from steel or other suitable material, and first caps 28A and 28B and second caps 34A and 34B may constructed from rubber or other similar material, preferably having high friction characteristics.

Cycle trainer 1 also includes connectors 40A and 40B that connect the bicycle 3 to the cycle trainer 1 and support the bicycle 3 with the rear tire 12 spaced above the floor surface 32 such that a user can push on the pedals 16 and rotate the rear wheel 8 of bicycle 3 without causing the bicycle 3 to move. A handle 14 is mechanically connected to connector 40B by linkage (not shown). Handle 14 can be rotated to shift connector 40B inwardly to engage the rear skewer 13 to hold bicycle 3 on cycle trainer 1.

With further reference to FIG. 2, cycle trainer 1 includes a bracket structure or arm 42 having a first end portion 44 that is rotatably connected to a rigid upright portion 46 of frame 20. A roller 48 is rotatably connected to a second end portion 50 of arm 42. As discussed in more detail below, roller 48 is operably connected to a force-generating device 58 that provides a resistance force as roller 48 rotates to thereby provide a resistance force to a user pushing on pedals 6. In use, roller 48 engages rear tire 12. Arm 42 may include first and second side plates 52A and 52B that are interconnected by a transverse plate 54. End portions 53A and 53B of first and second plates 52A and 52B, respectively, form a clevis-type connection with a bolt or pin 55 to pivotably connect the arm 42 to the frame 20 for rotation about a first horizontal axis “A” (see also FIG. 4). Roller 42 is rotatably mounted to second or forward portion 50 of arm 42 by a bearing 56 such that the roller 48 rotates about a second horizontal axis “B” (see also FIG. 4).

Referring again to FIG. 2, a height adjustment mechanism 60 adjusts the initial or starting height of roller 48. This ensures that the roller 48 engages rear tire 12 such that roller 48 rotates upon rotation of rear wheel 8 of bicycle 3. As discussed below, a knob 62 is fixed to a threaded rod 64 such that rotation of knob 62 rotates threaded rod 64 to adjust the preload of springs 80 and 82, which generates a moment acting on arm 42. A rigid backing plate 68 is secured to frame 20, and extends parallel to threaded rod 64. Nut 66 may include a flat side surface 67 (FIG. 3A) that slidably engages a flat surface 69 of plate 68 to thereby prevent rotation of nut 66 relative to backing plate 68, but permitting movement of nut 66 along threaded rod 64 as threaded rod 64 is rotated.

Threaded rod 64 includes an upper portion 74 having right hand threads, and a lower portion 76 having left hand threads. Nut 66 includes right hand threads that threadably engage upper portion 74 of threaded rod 64. A threaded plate 70 includes a flat surface 71 (FIG. 3B) that slidably engages front surface 69 of backing plate 68 such that the threaded plate 70 moves vertically upon rotation of threaded rod 42 without rotating with threaded rod 42. Threaded plate 70 includes a threaded opening 78 having left hand threads that threadably engage threaded lower portion 76 of threaded rod 64. A first or upper coil spring 80 extends between nut 66 and transverse plate 54, and a second or lower spring 82 extends between threaded plate 70 and transverse plate 54. Upper spring 80 is compressed, and provides a downwardly-acting biasing force acting on transverse plate 54 of arm 42. Lower spring 82 is also compressed, and generates an upwardly-acting biasing force on plate 54 of arm 42.

Referring again to FIG. 3, the nut 66 includes a bore or cavity 84 that receives a button 86 and compression spring 88. Button 86 includes a first surface portion 90A that is spaced apart from threads 65 of threaded rod 64. The first surface portion 90A is not threaded. A second portion 90B of button 86 includes threads 94 that are configured to threadably engage threads 65 of threaded rod 64. Spring 88 biases the threads 94 of second portion 92 into engagement with threads 65 of threaded rod 64. Nut 66 includes first and second clearance openings 95 and 96 that permit nut 66 to slide along threaded rod 64 when threads 94 of button 86 are disengaged from threads 65 of threaded rod 64.

To adjust the initial height of roller 48 (FIG. 2), a user pushes on button 86 in the direction of the arrow “A1” (FIG. 3) to shift the threads 94 of button 86 out of engagement with threads 65 of threaded rod 64. The nut 66 can then be moved along rod 64 as shown by the arrow “A2.” Once the proper adjustment of the roller height is obtained, a user releases button 86, and spring 88 causes threads 94 of button 86 to threadably engage threads 65 of threaded rod 64. A user can then rotate knob 62 to move nut 66 and threaded plate 70 along threaded rod 64 to adjust the compression of springs 80 and 82. Rotation of threaded rod 64 causes nut 66 and threaded plate 70 to shift in opposite directions due to the oppositely-handed threads of upper and lower portions 74 and 76, respectively. Thus, rotation of knob 62 simultaneously to adjusts the preload of springs 80 and 82. Springs 80 and 82 may have the same spring constant, and the upper and lower portions 74 and 76 of threaded rod 64 may have the same thread pitch. Thus, rotation of knob 62 causes equal increases and decreases in preload force of springs 80 and 82 acting on arm 42.

With further reference to FIG. 4, upper spring 80 (FIG. 2) provides a force 80A acting downwardly on arm 42, and lower spring 82 (FIG. 2) generates a force 82A acting upwardly on arm 42. Roller 48 contacts tire 12 at a contact point 100. Force-generating device 58 generates a resistance force such that roller 48 generates a force F1 acting on tire 12 in a direction that is opposed to the rotation of wheel 8, and tire 12 generates a force F2 acting on roller 48 in a direction opposite to force F2. The forces F1 and F2 act along a force tangent line 105 that passes through contact point 100. Arm 42 defines a centerline 43 that passes through the horizontal axes A and B. Normal forces F3 and F4 act on roller 48 and tire 12, respectively through contact point 100. The cycle trainer 1 is configured such that the contact point 100 is not normally aligned with the axis 43 in use. The contact point 100 and first axis A define an effective lever arm 110 shown by the straight dashed line extending through axis A and contact point 100 in FIG. 4. The effective lever arm 110 forms an angle θ relative to the force tangent line 105. Cycle trainer 1 is preferably configured such that the angle θ is less than 90°. The force tangent line 105 forms an angle α with respect to the centerline 43 of arm 42. The angle α is preferably less than 90°, such that the forces F2 and F3 applied to roller 48 produce a compressive force in arm 42.

In use, as a rider applies increasing force to pedals 16 of bicycle 3, forces F1-F4 will also increase due to the resistance force of force-generating device 58. Because the normal forces F3 and F4 increase, the roller 48 is driven more forcefully into contact with tire 12, thereby preventing slipping of tire 12 on roller 48. Because roller 48 has a rigid outer surface whereas tire 12 is somewhat resilient, contact point 100 may move along an arc 102 about horizontal axis A as the forces F1-F4 increase and decrease. Alternatively, roller 48 may have a resilient construction, in which case the contact point 100 may shift along, for example, force tangent line 105 if roller 48 and tire 12 have substantially equal resilience.

In use, a user can initially bring the roller 48 into contact with tire 12 by pushing button 86 of nut 66 to thereby shift the position of the arm 42 as discussed above. Adjustment of knob 62 and preload forces 80A and 82A (FIG. 4) acting on arm 42 varies the amount by which arm 42 rotates about axis A due to changes in the forces F1-F4. Thus, knob 60 can be rotated to ensure that roller 48 remains in contact with tire 12 without slipping, but also without excessive forces that would unduly increase the rolling resistance of trainer 1. For example, if a user notices that tire 12 slides on roller 48 when large forces are applied to pedals 16, a user can rotate knob 60 to adjust the forces 80A and 82A, thereby causing arm 42 to rotate a greater distance upon applying increased forces to pedals 16. The increased rotation of arm 42 in response to increased forces on pedals 16 results in larger normal forces F3 and F4 relative to the tangent forces F1 and F2, thereby reducing the tendency of the tire 12 to slide on roller 48.

Referring again to FIG. 2, force-generating device 58 may comprise a flywheel 104 that is connected to roller 48 by a shaft 106 or other mechanical arrangement. The force-generating mechanism 58 may also or alternatively include additional force-generating features/mechanisms to control the resistance force of roller 48. This additional resistance mechanism may comprise an eddy magnet 108 as discussed in more detail below in connection with FIG. 5. Alternatively, friction pads, fluid resistance, electromagnets, or other suitable resistance-generating mechanisms (not shown) may be utilized. In general, the flywheel 104 provides inertial force resistance to at least partially simulate the effects of inertia while riding bicycle 3 on a road surface or the like, and the eddy magnet 108 or other force-generating mechanism provides additional resistance force as required by a user.

Referring again to FIG. 5, eddy magnet 108 may be mounted to frame 2 by first and second brackets or supports 112 and 114, respectively. A threaded member such as nut and bolt assembly 118 passes through slot 116 in support 114 to permit adjustment of a position of eddy magnet 108 relative to outer surface 120 of flywheel 104. Flywheel 104 may comprise steel or other conductive material, such that rotation of flywheel 104 relative to eddy magnet 108 generates a resistance force acting on flywheel 104. The resistance force produced by eddy magnet 108 at a given flywheel rpm can be adjusted by shifting the position of eddy magnet 108 relative to outer surface 120 of flywheel 104. Flywheel 104 may be mounted on shaft 106 such that movement of arm 42 during use causes flywheel 104 to move (rotate) about first axis A as the forces F1-F4 vary due to variations in user forces applied to pedals 16. As flywheel 104 moves, the position of outer surface 120 of flywheel 104 relative to eddy magnet 108 changes. The position and geometry of eddy magnet 108 can be adjusted such that as arm 42 rotates due to increased user force on pedals 16, the outer surface 120 of flywheel 104 shifts closer to eddy magnet 108, thereby increasing the resistance force. Also, adjustment of preload forces 80A and 82A (FIG. 4) can be adjusted by rotating knob 62 (FIG. 2) to thereby adjust the simulation of inertial and momentum effects.

The magnitude of the eddy currents due to eddy magnet 108 vary directly with the distance between eddy magnet 108 and outer surface 120 of flywheel 104. The air gap distance/actuation is controlled by the preload forces 80A and 82A resulting from springs 80 and 82, respectively. As discussed above, the tension (preload force) of the springs 80 and 82 are controlled and adjusted utilizing knob 62. The lower the preload forces 80A and 82A, the greater the simulation of inertial and momentum effects. If the preload forces 80A and 82 are increased, the simulation of inertial and momentum effects is reduced. In general, larger riders require lower preload forces 80A and 82, and smaller riders require larger spring tensions/preload forces 80A and 82A. The combined inertial and momentum effects increase the effective mass of the flywheel 104 to thereby simulate real motion for humans riding a non-stationary bicycle 3 on a road surface, or to thereby simulate real motion for humans performing another activity such as rowing a boat, riding an outdoor elliptical machine, or riding a recumbent bicycle.

Changes (adjustment) of inertial effects to account for riders having different weights can also be achieved by utilizing an adjustment mechanism (not shown) to shift the position of springs 80 and 82 relative to axis A of arm 42. For example, if springs 80 and 82 are shifted (adjusted) to increase the distance of springs 80 and 82 relative to axis A, the effective stiffness of springs 80 and 82 (i.e. the force required to rotate arm 42 about axis A) will decrease such that for a given force applied to pedals 16, the rotation of arm 42 will increase, thereby increasing the inertia modeling (simulating) effects to simulate increased rider mass/weight. Conversely, adjusting the position of springs 80 and 82 to reduce the length of the moment arm of springs 80 and 82 about axis A will increase the effective stiffness of springs 80 and 82, thereby reducing the inertia modeling effects to more accurately simulate decreased rider mass/weight. It will be understood that adjustment of the inertia modeling effects to account for changes in rider mass/weight may also be accomplished utilizing non-linear springs 80 and 82 (i.e. springs that are not governed by a linear equation of the form F=kΔx), cam mechanisms, etc.

The following is an example of a typical rider's energy on a road bike and the energy stored in a flywheel of a typical stationary trainer. The kinetic energy of a road bike is:

E _(k)=1/2mv ²

-   -   For a 165 lb. rider on a 15 lb. road bike at 17 mph, this is:

Joules of 165 lb. rider at 17 MPH on a road bike 2368.16

It will be understood that the rotational kinetic energy of the wheels and other rotating components will provide some additional kinetic energy.

For a typical prior art stationary trainer the kinetic energy is as follows:

Mass of flywheel on typical prior art stationary 2.84 kg trainer Radius of flywheel of typical prior art stationary 0.08 m trainer Moment (.5 × mass *radius{circumflex over ( )}2) 0.01 kg-m{circumflex over ( )}2 Pedal Speed (RPM) 76.00 rev/min Drive Ratio 35.00 i.e. 35:1 Flywheel Speed (RPM) 2660.00 rev/min Flywheel Speed (RPS) 44.33 rev/sec Flywheel Speed (rad/s) 278.41 radians/sec Joules on Typical prior art Mechanical Trailer 319.56

In the illustrated example, a 165 lb. rider at 17 mph will have about 2368 joules of energy on a road bike. However, the flywheel of a typical stationary mechanical trainer will only have about 319 joules of energy during use. Accordingly, typical prior art trainers that utilize only a flywheel only have a small amount of stored kinetic energy relative to a rider on a road bike that is moving. Thus, known stationary trainers that utilize flywheels without providing variable force do not store sufficient kinetic energy to accurately simulate the effects of momentum that are experienced on a moving road bike.

With further reference to FIG. 6, a cycle trainer 1A according to another aspect of the present invention includes a frame 2A that includes frame members 22A and 22B that connect to a bicycle 3 in substantially the same manner as described above in connection with the trainer 1 of FIGS. 1 and 2. Trainer 1A includes an arm 42A that is rotatably mounted to frame 2A for rotation about a first axis AA. A roller 48A is rotatably mounted to arm 42A for rotation about a second axis BB. Roller 48A is configured to engage tire 12 of a bicycle 3 in substantially the same manner as described above in connection with FIGS. 1 and 2. A height adjustment knob 62A is connected to a threaded rod 122 that threadably engages a threaded member 124 that is mounted on arm 42A. Lower end 126 of threaded rod 122 is rotatably connected to frame 2. Due to the threaded engagement of threaded rod 122 with threaded member 124, rotation of adjustment knob 62A causes arm 42A to pivot about first horizontal axis AA to adjust the height of arm 42A and roller 48A. Threaded rod 122 does not include both left and right hand threaded portions, and rotation of adjustment knob 62A is only utilized to adjust the position of roller 48A relative to tire 12.

Trainer 1A also includes a resistance adjustment knob 128 that is connected to a threaded rod 130 having a first portion 132 with right-handed threads, and a second portion 134 having left hand threads. First and second square nuts 136 and 138 threadably engage first and second threaded portions 132 and 134, respectively, and also slidably engage a backing plate 140 that is fixed to frame 2A. First and second springs 142 and 144, respectively act on a washer member 146 that is positioned between springs 142 and 144. Washer member 146 is not threaded, and is therefore free to slide along threaded rod 130, subject to forces acting on washer 146 due to compression of springs 142 and 144. A lever arm 148 includes a first end 150 that is pivotably connected to frame 2 for rotation about a pivot point 151. Lever arm 148 is pivotably connected to washer member 146 at pivot point 152 by a pin or other suitable connector (not shown). An eddy magnet 154 is mounted to outer end 156 of lever arm 148 adjacent an outer surface 120A of flywheel 104A. Flywheel 104A is rotatably mounted to frame 2 for rotation about the second axis BB. As discussed above, the position or height of arm 42A is fixed at a desired position by rotation of adjustment knob 62A. Thus, in use, the position of arm 42A does not change, and the position of second axis BB also does not change.

Referring again to FIG. 6, the pivot point 151 of lever arm 148 is offset a distance “X” from the second axis BB. Thus, rotation of lever arm 148 changes the distance between eddy magnet 154 and outer surface 120A of flywheel 104A. In use, rotation of tire 12 causes roller 48A and flywheel 104A rotate. Rotation of flywheel 104A generates forces due to eddy magnet 154. The forces act along a force tangent line 105A. The forces acting on flywheel 104A and eddy magnet 154 are equal and opposite, and act along force tangent line 105A. The forces acting on eddy magnet 154 cause the lever arm 148 to rotate about pivot point 151. Because pivot point 151 is not aligned with pivot point 152, the distance between eddy magnet 154 and outer surface 120A of flywheel 104A varies as a user applies more or less force to pedals 16. Accordingly, the resistance force varies due to changes in a rider's applied force, thereby simulating the effects of inertia and momentum.

Prior to use of trainer 1A, a user can rotate resistance adjustment knob 128 to thereby change the initial position of lever arm 148 and thereby adjust the position of eddy magnet 154 relative to outer surface 120A of flywheel 104A. For example, the components may be configured such that clockwise rotation of knob 128 causes the eddy magnet 154 to move closer to outer surface 120A of flywheel 104A, which increases the magnitude of eddy currents developed during use of trainer 1A, thereby increasing resistance acting on roller 48A. An adjustment knob 158 can be utilized to rotate the first and second portions 132 and 134 of threaded rod 130 to thereby adjust the preload of springs 142 and 144. Thus, the adjustment knob 158 can be utilized to adjust the momentum effects experienced by a rider. Specifically, greater preload of springs 142 and 144 can be utilized if less motion of lever arm 148 is required, and lower spring tension can be utilized if greater movement of lever arm 148 is required. In general, the momentum effects can be adjusted for a rider's weight as discussed in more detail above. Coupling 160 joins rods 130 and 134 and allows them to turn independently such that knobs 128 and 158 also turn independently.

In the trainer 1A of FIG. 6, the magnitude of eddy currents vary directly with the air gap distance between the eddy magnet 154 and the outer surface 120A of flywheel 104A. The air gap distance varies with forces along the force tangent line 105A, which vary with pedal forces. The air gap distance/actuation is controlled by the tension of the springs 142 and 144 as noted above. The tensions of the springs 142 and 144 are adjusted by the inertia/momentum knob 158. Lower spring tensions provide greater simulation of inertial and momentum effects. Conversely, greater spring tensions reduce the simulation of inertial and momentum effects. As discussed above, larger riders generally require lower spring tensions, and smaller riders generally require greater spring tensions.

The net effect of the inertial and momentum effects is to increase the effective mass of flywheel 104A as required to simulate real motion for a human riding a bicycle 3 on a road surface. The inertia/momentum knob 158 may include a torque measurement device (not shown) similar to a torque wrench, and the masses of riders may be correlated with known torques. Also, the masses (weights) of riders may be written on the knob 158 such that a user can simply rotate the knob 158 to the position corresponding to the rider's weight. The resistance force opposing motion of the user is provided by the eddy magnet 154 (FIG. 6), either by itself or in combination with another fixed eddy magnet (not shown) that could be positioned, for example, inside flywheel 104A. Eddy magnet 154 may also be utilized in combination with a fluid-type brake or a friction pad (not shown). These types of known resistance devices are typically speed sensitive, and increase the resistance force based on rpm. This is in contrast to the resistance force generated by moving lever arm 148 and eddy magnet 154, which provides increasing resistance force based on applied forces to the pedals 16 (FIG. 1) of a bicycle 3 that is mounted to the trainer 1A.

Resistance devices that provide increased force with increased speed (e.g. friction pads) may be utilized to simulate a portion of the effects of increased rolling resistance, wind resistance, and/or other resistance forces experienced by riders that increase based upon speed, and movable eddy magnet 154 may be utilized to further simulate those effects, as well as simulate inertia/momentum (i.e. force-varying) effects.

With further reference to FIG. 7, a stationary exercise device such as an indoor cycle 162 includes a frame 164, handle bars 166, a seat 168, and one or more movable input members such that receive input forces from a user. The movable input members may comprise pedals 170A and 1706. A drive system may include a chain or belt 172 that operably connects a wheel or pulley 174 to a movable output member such as a flywheel 174. Indoor cycle 162 includes a lever arm 176 that is pivotably mounted to frame 164 at a first pivot point 178. An eddy magnet 180 is mounted to an outer end 182 of lever arm 176. Flywheel 174 rotates about axis 184. Axis 184 is spaced apart from first pivot point 178, such that rotation of lever arm 176 causes a distance between eddy magnet 180 and outer surface 186 of flywheel 174 to vary, thereby varying the resistance force generated due to eddy magnet 180. Eddy magnet 180 thereby provides a resistance force that varies as a function of forces applied to pedals 170A, 170B to simulate inertia/momentum effects. A resistance knob 188 is connected to a threaded rod 190. A coupling 192 is mounted to the frame 164 by a bracket 194. An inertia/momentum adjustment knob 196 is operably connected to threaded rod 190. First and second springs 198 and 200 provide forces acting on lever arm 176 to provide variable momentum effects to account for different rider weights.

Rotation of adjustment knob 188 sets the initial position of eddy magnet 180 relative to outer surface 186 of flywheel 174, and rotation of inertia/momentum knob 196 adjusts the preload tension of springs 198 and 200 in substantially the same manner as discussed above in connection with FIGS. 1-6.

Eddy magnet 180 generates a resistance force acting along force tangent 105B tending to resist rotation of flywheel 174. The resistance knob 188 can be utilized to adjust the air gap between magnet 180 and outer surface 186 of flywheel 174 to increase or decrease the initial resistance force generated upon rotation of flywheel 174. Adjustment of inertia/momentum knob 196 adjusts the momentum effects as required to account for the weight of an individual rider. Accordingly, the indoor cycle 162 provides simulation of momentum effects in substantially the same manner as described above in connection with the cycle trainers 1 and 1A.

Exercise devices according to the present disclosure provide variable resistance force that simulates inertia and/or momentum in a manner that does not require sensors, a controller, and/or powered actuators. Because the resistance member (e.g. eddy magnet) is mechanically connected to the one or more input members (e.g. pedals), variable forces acting on the one or more input members generates a variable resistance force due to movement of the resistance member relative to one or more output members (e.g. flywheel). The flywheel or other output member may be integrally formed with the one or more input members.

It is to be understood that variations and modifications can be made on the aforementioned structure without departing from the concepts of the present invention, and further it is to be understood that such concepts are intended to be covered by the following claims unless these claims by their language expressly state otherwise. 

The invention claimed is:
 1. A cycle trainer for generating a resistance force in a bicycle when a bicycle is connected to the cycle trainer, the cycle trainer comprising: a support structure configured to engage and support a bicycle in a stationary position in which a rear wheel of the bicycle does not engage a floor surface when the rear wheel rotates about a rear axis of the bicycle; a bracket structure pivotably connected to the support structure for rotation about a first axis; a roller having an outer diameter, wherein the roller is rotatably mounted to the bracket structure about a second axis; a resistance mechanism configured to provide a rotational resistance force that resists rotation of the roller; and wherein the roller is configured to engage a rear tire of a bicycle at a contact point to define a force tangent line extending through the contact point that is tangent to an outer diameter of the rear tire and the outer diameter of the roller, and wherein an effective lever arm line is defined that extends linearly through the contact point and the first axis, and wherein the force tangent line and the effective lever arm line define an acute angle therebetween such that a compressive force is applied to the bracket structure by the roller in use.
 2. The cycle trainer of claim 1, wherein: the roller is configured to be biased into engagement with a rear tire of a bicycle when a bicycle is connected to the cycle trainer.
 3. The cycle trainer of claim 2, wherein: the bracket structure rotates about the first axis in response to variations in force applied to the roller by a rear tire of a bicycle.
 4. The cycle trainer of claim 3, wherein: the resistance mechanism is operably connected to the bracket structure such that a magnitude of the rotational resistance provided by the resistance mechanism is a function of a position of the bracket structure relative to the support structure to thereby at least partially simulate the effects of inertia and/or momentum.
 5. The cycle trainer of claim 4, wherein: the bracket structure is configured to rotate upwardly due to increased force being applied to the roller by a rear tire of a bicycle.
 6. The cycle trainer of claim 5, including: a first spring member that rotationally biases the bracket structure downwardly in a first direction; a second spring member that rotationally biases the bracket structure upwardly in a second direction whereby the bracket structure is biased towards an initial position; and an adjustment mechanism that adjusts a magnitude of first and second spring preloads of the first and second springs, respectively.
 7. The cycle trainer of claim 6, including: a height adjustment mechanism that is operably connected to the bracket structure to provide adjustment of an initial rotational position of the bracket structure relative to the support structure about the first axis.
 8. The cycle trainer of claim 7, wherein: the height adjustment mechanism comprises a threaded rod, a collar slidably disposed on the threaded rod, a threaded member movably engaging the collar whereby the threaded member can be selectively disengaged from the threaded rod, and a spring biasing the threaded member into engagement with the threaded rod.
 9. The cycle trainer of claim 4, wherein: the resistance mechanism includes a wheel having an electrically conductive portion, wherein the wheel is operably connected to the roller such that rotation of the roller causes the wheel to rotate; the resistance mechanism includes a magnet disposed adjacent the electrically conductive portion of the wheel such that the magnet generates eddy currents upon rotation of the wheel to provide a variable rotational resistance force acting on the roller; and wherein rotational movement of the bracket structure causes a position of the magnet relative to the electrically conductive portion of the wheel to change and thereby change the rotation resistance force.
 10. The cycle trainer of claim 9, wherein; the wheel is mounted to the bracket structure and the magnet is mounted to the support structure such that rotational movement of the bracket structure shifts the wheel relative to the magnet.
 11. The cycle trainer of claim 4, wherein: the resistance mechanism includes a wheel that is operably connected to the roller such that rotation of the roller causes the wheel to rotate; the resistance mechanism includes a friction brake that is configured to generate a frictional rotational resistance force acting on the roller that varies as a function of the position of the bracket structure relative to the support frame.
 12. The cycle trainer of claim 1, wherein: the resistance mechanism comprises a wheel that is operably connected to the roller such that the roller causes the wheel to rotate, the resistance mechanism further including a resistance member that is movably disposed adjacent to the wheel to generate a variable resistance force acting on the wheel.
 13. The cycle trainer of claim 12, wherein: the resistance mechanism is configured such that the variable resistance force increases as force applied to the roller by a bicycle tire increases.
 14. The cycle trainer of claim 13, wherein: the wheel includes a conductive portion; the resistance member comprises an eddy magnet that is configured to move relative to the conductive portion of the wheel due to forces acting on the eddy magnet generated by rotation of the wheel.
 15. The cycle trainer of claim 14, including: an adjustment assembly configured to retain the bracket structure at a selected position relative to the support structure with the roller engaging a rear tire of a bicycle.
 16. The cycle trainer of claim 15, wherein: the adjustment assembly comprises a threaded member that interconnects the bracket structure to the support structure.
 17. A stationary exercise device, comprising: a support structure; at least one input member movably connected to the support structure; a wheel rotatably mounted to the support structure and operably connected to the at least one input member such that movement of the at least one input member causes the wheel to rotate; an arm pivotably mounted to the support structure; a resistance member mounted on the arm, wherein the resistance member interacts with the wheel when the wheel is rotating to generate a variable resistance force tending to prevent rotation of the wheel, and wherein changes in forces applied to the at least one input member cause the arm to pivot and change the resistance force.
 18. The stationary exercise device of claim 17, wherein: the wheel defines a circular outer periphery and rotates about a wheel axis; the arm pivots about a pivot axis; the pivot axis is offset from the wheel axis such that the resistance member moves radially relative to the circular outer periphery of the wheel as the arm pivots.
 19. The stationary exercise device of claim 18, including: a biasing member that biases the resistance member away from the circular outer periphery of the wheel.
 20. The stationary exercise device of claim 19, wherein: the resistance member comprises an eddy magnet.
 21. The stationary exercise device of claim 19, wherein: the resistance member comprises a brake pad that engages the wheel.
 22. The stationary exercise device of claim 17, wherein: the stationary exercise device comprises a stationary exercise bike.
 23. The stationary exercise device of claim 17, wherein: the stationary exercise device comprises a road bike in combination with a cycle trainer, wherein the road bike includes a rear tire that is driven by the pedals, and wherein the cycle trainer includes a roller that is operably connected to the wheel, and wherein the roller engages the rear tire of the road bike whereby rotation of the rear tire causes the roller and wheel to rotate.
 24. A method of controlling stationary exercise equipment having one or more movable input members that move in response to user forces applied to the one or more movable input members, wherein the one or more movable input members are operably connected to one or more movable output members such that a resistance force acting on the one or more movable output members changes user forces required to move the one or more movable input members, the method comprising: utilizing a resistance member that moves relative to the one or more movable output members to provide a resistance force acting on the resistance member and the one or more movable output members, wherein the resistance force varies as a function of the position of the resistance member relative to the one or more movable output members; utilizing the resistance force acting on the resistance member to move the resistance member relative to the one or more movable output members to vary the resistance force to thereby vary user forces required to move the one or more movable input members in a manner that at least partially simulates the effects of one or more of momentum and/or inertia.
 25. A stationary exercise device comprising: at least one movable member; and a resistance member that is mechanically connected to the at least one movable member and moves due to forces applied to the at least one movable member by a user, and wherein movement of the resistance member produces a variable resistance force acting on the at least one movable member to at least partially simulate at least one of inertia and/or momentum.
 26. The exercise device of claim 25, including: a wheel defining a circular outer periphery, wherein the wheel rotates about a wheel axis; an arm that pivots about a pivot axis; the pivot axis is offset from the wheel axis such that the resistance member moves radially relative to the circular outer periphery of the wheel as the arm pivots.
 27. The exercise device of claim 26, including: a biasing member that biases the resistance member away from the circular outer periphery of the wheel.
 28. The exercise device of claim 27, wherein: the resistance member comprises an eddy magnet.
 29. The exercise device of claim 26, wherein: the resistance member comprises a brake pad that engages the wheel. 